In the Sitecom, click on "Internet Settings", then "IPv6 Settings". Choose "6RD" in the firs drop down option

Then fill out the Sitecom form as in the screendump below

It should now work. So, with your laptop/PC, go to http://test-ipv6.com/ to see if you have IPv6 connectivity. That site should say something like "Your IPv6 address on the public Internet appears to be 2001:470:... (HURRICANE - Hurricane Electric, Inc.)".Screendump (click for larger image):

The throughput over Wifi is quite impressive: I get 11,3 MB/s, thus about 113 Mbps. (on my 300/300 Mbps Internet connection). See this output: